Before this specimen I had never seen a "bird's nest fungus", and this was noticed quite accidently as I walked across Wanstead Flats. It is a very small fungus, and I only noticed it because of its very dark colour against the bright moss surrounding it.

Apparently quite common, these are often overlooked because of their small size, this group of four being only something like 2cm across.

An "egg" - the spore-containg vessel - can be seen in the top right-hand fruit-body.